photo by kqedquest (Flickr Creative Commons)

I’ve assumed that transport via boat, whether shipping goods or people, is less polluting and has a lower carbon footprint than flying or road freight, for example. Not so, according to both scientific research and inside information from the maritime shipping industry.

While diesel cars – once known as smelly, noisy polluters – have relatively cleaned up their act to the level of standard petrol or gasoline-fuelled cars, the heavy-duty diesel and low-grade fuel oil engines that power ships are a scourge on the environment and human health.

From an article in the Economist:

Research by James Corbett of the University of Delaware estimates that soot from ships’ diesels contributes to 60,000 deaths from and lung disease every year. Dirty ships’ diesels also produce oxides of nitrogen—the main ingredient of smog.

It is estimated that cargo ships currently produce 30% of the world’s nitrogen-oxide emissions.

But there may be a partial solution – and it’s as simple as H2O. Experiments have shown that mixing water with diesel and adding a surfactant – which prevents the oil and water from separating – eliminates soot and reduces nitrogen-oxide emissions by up to 80%.

Successful implementation of this technology, along with the new air quality standards in both Europe and the US, would be good news for both the environment and world health. According to an article in the Guardian from last year, a US study has shown that pollution from the world’s 90,000 cargo ships causes 60,000 deaths annually in that country alone and ‘$330bn (€260bn) per year in health costs from lung and heart diseases’. A Danish government study claims it costs Denmark £5bn (€6bn) per annum in health costs and .1% of Danes to die prematurely each year.

Confidential data from maritime industry insiders based on engine size and the quality of fuel typically used by ships and cars shows that just 15 of the world’s biggest ships may now emit as much pollution as all the world’s 760m cars.


That’s over 50 million cars per big ship.

Additional resources:

Treehugger – Could we Clean Up Air Pollution from Cargo Ships with… H2O?!